Vacuum control devices



Jan. 13, 1959 1 5 E. E. MODES 2,858,459

' VACUUM CONTROL DEVICES Filed Feb. 8, 1956 United States Patent DVACUUM CONTROL DEVICES 'Edward E. Modes, Chicago, Ill., assignor to TheDole Valve Company, Chicago, Ill., a corporation of Illinois ApplicationFebruary 8, 1956, Serial No. 564,284 3 Claims. (C1. 236-81) Thisinvention relates to improvements in vacuum control devices and moreparticularly relates to an improved form of vacuum control devicecontrolling the vacuum from the intake manifold of an internalcombustion engine to a vacuum motor in accordance with temperatureconditions.

A principall object of the invention is to provide a novel and improvedform of vacuum control deviceV arranged to cope with the variable vacuumconditions encountered in internal combustion engines and to control thevacuum to a Vacuum motor in accordance with temperature conditions andthe setting of the device.

Another object of the invention is to provide a new and improved form ofvacuum equalizing and control valve arranged to equalizethe vacuumsupplied by the intake manifold of an internal combustion engine and tovary the vacuum in accordance with variations in temperature determinedby the setting of the device.

A further and more specic object of my invention is to provide a novelform of vacuum control device in which a bi-metal temperaturesensitiveelement works against a pneumatic two-valve force balancingdevice and applies a compressive force thereto to control the vacuum inaccordance with the temperature setting of the bi-metal element. l

These and other objects of the invention will appear from time to timeas the following specification proceeds and with reference to theaccompanying drawings wherein:

Figmre 1 is a top plan view of a vacuum control device constructed inaccordance with my invention;

Figure 2 is an end view of the device shown in Figure 1; and

Figure 3 is a partial fragmentary sectional view of the device shown inFigure 1 and looking substantially along line lII-III of Figure 1, lbutshowing a portion of the control cam therefor in side elevation.

In the drawings, a vacuum control valve 10, which may be mounted withinthe passenger compartment of an automotive vehicle, is shown ascomprising a valve casing 11 having a vacuum equalizing chamber 12therein with an inlet or vacuum output passageway 13 leading into saidchamber through a wall thereof and adapted to be connected to a vacuummotor and the like (not shown) to supply vacuum thereto to operate thesame. The vacuum equalizing chamber 12 has a central annular wall 1Sextending upwardly from the bottom thereof and encircling a port 16connected with a source of vacuum through an outlet passageway 17. Theoutlet passageway 17 may be connected with the intake mamfold of aninternal combustion engine, which serves to supply vacuum to the chamber12 and the inlet or vacuum output passageway 13.

The opposite end of the vacuum equalizing chamber 12 from the port 16 isshown as being closed by a diaphragm 19 having a depending annular rib20 recessed within an annular recessed portion 21 of the top wall of thevalve casing 11 and sealed thereto as by a retainer yoke 23 ICCgenerally annular in form and extending about the diaphragm 19 andcrimped or otherwise secured tothe The wall 27 of the diaphragm 19 isabutted at itsV outer end by a leg 32 of a generally U-shaped1iii-metallic thermal element 33, applying a compressive force to saiddiaphragm. The leg 32 has a passageway 35 leading therethroughconcentric with the port 29, for the passage of` air at atmosphericpressure within the chamber 12 to balance the vacuum within saidchamber, as will hereinafter moreclearly appear as this specificationproceeds. The port 29 is engaged by a valve 36 having a stem 37extending through said port.V The inner end of the stem 37 is shown asbeing generally conical in form and as forming a valve 39 engaging theport 16 and closing the chamber 12 to a source of vacuum. A conicalspring 411 encirclcs the stem 37 and is interposed between the undersideof the diaphragm 19 and a collar 41 on said stem to bias` the valve 36in a closed position, and to accommodate opening of said valve and theport 29 upon inward movement of the diaphragm 19, effected by operationof the thermal element 33 upon increases in temperature, or effected byhigh vacuum conditions within the chamber 12, drawing the diaphragm 19within said chamber. The spring 40 is undersufiicient Compression tobias the valve 36 to seal the port 29 tightly.

A helical spring 43 is shown as encircling the annular Wall 15 and asbeing seated in the bottom of the chamber 12 at one end and as engagingthe` underside of the diaphragm 19 at its opposite end, to tend `to movethe diaphragm 19 against the leg 32 of the bi-metallic thermal element33. VThe helical spring 43 is loaded suiiciently to exert an outwardforce on the diaphragm equivalent to maximum atmospheric pressure timesthe effective area of the diaphragm. l

The bi-metal thermal element 33 is shown as having ears 44 extendinginwardly from the base of the U between the leg 32 and an upper leg 45thereof. The ears 44 are pivoted to lugs 46 `extending upwardly from abracket 47 formed integral with the yoke 23 and ex-` tending outwardlytherefrom. A pivot pin 49 pivotally connects the ears 44 to the lugs 46.p

The upper leg 45 of the biametallic thermal element 33 is shown ashaving a rib 50 formed therein and extending thereacross and upwardlytherefrom. The rib 50 terminates into an arm 51 extending laterallytherefrom and forming a cam rider engaging an internal Cam face 53formed in a pivoted cam member 54. The cam member 54 is pivotedintermediate its ends on a pivot pin 55 cxtending outwardly from thevalve casing 11.. The cam member 54 has an arm 56 depending from thepivot pin 55, to which may be connected an actuator for adjusting theposition of the cam member 54 and` the operating range of the bimetalthermal element and for holding said cam in its adjusted position. t

The bi-metal thermal element 33 is formed with itshig expanding side onthe inside of the element. Thus,`upon increases in temperature thecompressive force against the diaphragm 19 will increase and tend tomove said diaphragm against the spring 43 in adirection tounseat thevalve 36 and open the port` 29 to admit air at atmospheric pressure intothe chamber 12. Thus, if `the cam member 54 is moved in the clockwisedirection, "the tension on lthe bi-metal thermal element 33 and theforce with which said bi-metal thermal element bears against the innerwall 27 of the diaphragm 19 will be increased. The temperature at'whichsaid bi-metal thermal element operates to unseat the valve 35 from theport 29 will thus be reduced.

In a contrary manner, as the cam member 54 is moved inacounter-clockwise direction, the tension or" the bimetallicthermalel-ement 33 and the compressive force, exerted by said thermalelement against the diaphragm 19 will be decreased resulting in a longertravel or said thermal element to unseat the valve 36 from the port 29.This will raise the temperature at which the thermal element 33 operatesto unseat the valve 36 to admit air at atmospheric pressure into thechamber 12.

A stop 57 is shown as extending from the yoke 23 inwardly along theupper side of the leg 32 of the bimetal thermal elementvto limitexcessive deflection of the `diaphragm 19 and the leg 32 of the bi-metalthermal element 33 outwardly with respect to the casing 11 by the spring43, when the source of vacuum drops to zero.`

In operation of the device the controlled vacuum within the chamber 12will attain a value between Zero and that of the vacuum source, suchthat the downward force of the vaculnn on the diaphragm 19 times theeiective diaphragm area plus the downward force of the leg 32 of thebi-metal thermal element 33 on the diaphragm is equal to the upwardforce of the helical spring 43. The vacuum in the chamber 12 will thusbe a function of the downward force of the leg 32 of the bi-metalelement acting against the diaphragm 19.

Where a condition of equilibrium exists at the temperature to which thelai-metallic thermal element 33 has been set and the vacuum value in thechamber 21 is between zero and the vacuum value at the source of vacuum,if the temperature to which the bi-metal thermal element 33 is subjectedincreases, the balance between the bi-metal thermal element 33 and thediaphragm 19 will be disturbed. The leg 32 of the bi-metal thermalelement 33 will then deflect the diaphragm 19 against the spring 43.This will cause the diaphragm to move away from the valve 36 and unseatsaid valve and open the port 29. Air at atmospheric pressure will thenow through the passageway in the leg 32 of the bi-metal thermal element33 and through the port 29 into the chamber 12 and reduce the vacuumtherein.

As the vacuum is reduced in the chamber 12, the spring 43 will move thediaphragm 19 upwardly. This will deflect the leg 32 of the bi-metalelement 33 upwardly until the port 29 is again closed. A new conditionof equilibrium will then exist at a lower vacuum value and at a higherbi-metal temperature.

lIf the temperature to which the bi-metal thermal element 33 issubjected decreases, the leg 32 will move away from the `diaphragm 19.The spring 43 will then force the diaphragm to follow the leg 32. Thiswill lift the valve 39 from the port 16. The vacuum source will thenldraw air from the chamber 12 to increase the vacuum value therein untilthe d-iaphragm is again returned to its equilibrium position in whichthe ports 16 and 29 are closed.

While I have herein shown and described one form in which my inventionmay be embodied, it will be understood'that various modications andvariations of the invention may be eected without departing from thespirit and scope of the novel concepts thereof.

I claim as my invention:

1. In a temperature responsive vacuum control valve, a valve casinghaving a valve chamber therein, a port leading from said chamber andadapted to have connection with a source of vacuum, an inlet into saidchamber adapted to have connection with a vacuum motor and the like tosupply vacuum to operate the same, a diap hragm extending over saidchamber and having an annular wall extending outwardly therefrom, a portleading through said diaphragm within the margins of said wall forventing said chamber to atmosphere, valve means within the margins ofsaid wall in association with said ports and operated by movement ofsaid diaphragm inwardly and outwardly of said chamber and biased toclose said port leading through said diaphragm, a bi-metal thermalelement generally U-shaped in form, pivoted adjacent the base of the Uand having generally parallel legs extending over said diaphragm, andmeans reacting against one of said legs to retain said legs from outwardmovement with respect to the other of said legs and biasing the other ofsaid legs into engagement with said wall in outwardly spaced relationwith respect to said valve means and normally balancing said diaphragmto maintain both of said ports closed upon balanced conditions of thevacuum within said chamber in accordance with the temperature setting ofsaid thermal element, the high expanding side of said thermal elementbeing on the inside thereof to effect movement of said leg engaging saidwall in a direction to move'said diaphragm with respect to said valvemeans to open said port leading through said ydiaphragm uponpredetermined increases in temperature, and accommodating movement ofsaid diaphragm in an opposite direction to engage said valve meansandclose said port within said wall and open said port leading from saidchamber upon predetermined reductions in temperature,

2. In a temperature responsive vacuum control valve, a valve casinghaving a valve chamber therein, a port leading from said chamber andadapted to have connection with a source of vacuum, an inlet into said'chamber l adapted to have connection with a vacuum motor and the like,a diaphragm extending over said chamber and forming a movable wallthereof, land having a port therein opening from said chamber toatmosphere, said diaphragm having an annular wall encircling said portand extending outwardly therefrom, valve means within said annular wallin association with said diaphragm and ports, for closing both of saidports upon balanced conditions of vacuum within said chamber, abi-metal'thermal element U-shaped in form, pivoted adjacent the base ofthe U and having legs extending over said diaphragm in vertically spacedrelation with respect to each other, the lower of said legs havingengagement with said annular wall in outwardly spaced relation withrespect to said valve means, the high expanding side of said thermalelement` being on the inside thereof to effect movement of the lower ofsaid legs in a direction to move said diaphragrn with respect to saidvalve means and open the port therethrough upon predetermined increasesin temperature, an adjustable cam means engaging the upper of said legsand stressing said thermal element to bias the lower of said legs intoengagement with said annular wall, said cam means being adjustable tovary the force of engagea ment of the lower of said legs with saiddiaphragm and the temperature range of operation of said thermalelement, and a helical spring within said chamber having engagement withsaid diaphragm and balancing said thermal element for a condition ofequilibrium within said chamber in accordance with the temperaturesetting of said thermal element.

3. In a temperature responsive vacuum control valve, a valve casinghaving a valve chamber therein, a port leading from said chamber andadapted to have connection with a source of vacuum, an inlet into saidchamber adapted to have connection with a vacuum motor and the like, adiaphragm extending over said chamber and sealed thereto and having aport therein opening from said chamber to atmosphere, said diaphragmalso having an annular wall encircling said port and extending outwardlytherefrom, a single valve member extending through said port leading tosaid diaphragm and having a valve on the outside thereof within thelimits'of said annular wall and engageable with said port leadingthrough said diaphragm, said valve member also having a second valvespaced from said first valve within said chamber and engageable withsaid iirst port leading from said chamber, spring means biasing saidfirst valve into engagement with said port leading through saiddiaphragm, a bi-metal thermal element generally U-shaped in form havingits high expanding side on the inside thereof and pivoted adjacent thebase of the U and having vertically spaced legs extending over saiddiaphragm, means reacting against the upper of said legs and forming areaction member for said thermal element and stressing said thermalelement to bias the lower of said legs into engagement with said wall inspaced relation with respect to said iirst mentioned valve and reactingagainst said diaphragm with a -compressive force to move said diaphragminwardly upon predetermined increases in tempera ture to open said iirstvalve and admit air at atmospheric pressure within said chamber, and ahelical spring seated 6 within said chamber and engaging said diaphragmand biasing said diaphragm outwardly with respect to said chamberagainst the lower of the legs of said thermal element, to efect openingof Said second valve :and the increase of vacuum within said chamberupon predetermined reductions in temperature.

References Cited in the le of this patent UNITED STATES PATENTS 554,398Powers Feb. 11, 1896 2,356,970 Brockett Aug. 29, 1944 2,405,979Rosenberger Aug. 20, 1946 2,564,222 .Toesting Aug. 14, 1951 2,601,377Ellis June 24, 1952 2,663,499 Schutt Dec. 22, 1953 2,668,014 Lund Feb.2, 1954

